Methods of forming holes using mask pattern structures

Abstract

In a method of forming holes, a plurality of guide patterns physically spaced apart from each other is formed on an object layer. The guide pattern has a ring shape and includes a first opening therein. A self-aligned layer is formed on the object layer and the guide patterns to fill the first opening. Preliminary holes are formed by removing portions of the self-aligned layer which are self-assembled in the first opening and between the guide patterns neighboring each other. The object layer is partially etched through the preliminary holes.

What is claimed is: 
     
       1. A method of forming holes, the method comprising:
 forming a plurality of guide patterns physically spaced apart from each other on an object layer, each of the guide patterns having a ring shape and including a first opening therein; 
 forming a self-aligned layer in the first openings and between the guide patterns; 
 forming preliminary holes by removing portions of the self-aligned layer which are self-assembled in the first openings and between the guide patterns neighboring each other; and 
 partially etching the object layer through the preliminary holes. 
 
     
     
       2. The method of  claim 1 , wherein:
 the self-aligned layer is formed using a block copolymer that includes a first polymer unit and a second polymer unit different from each other, and 
 forming the self-aligned layer includes forming a first self-aligned pattern self-assembled at a central portion of each of the first openings and between the guide patterns neighboring each other, and a second self-aligned pattern self-assembled on a remaining portion of the object layer except for a portion of the object layer on which the first self-aligned pattern is formed, the first self-aligned pattern and the second self-aligned pattern including the first polymer unit and the second polymer unit, respectively. 
 
     
     
       3. The method of  claim 2 , wherein:
 the first self-aligned pattern includes a plurality of first pillars, each first pillar self-assembled at the central portion of one of the first openings, and each of a plurality of second pillars self-assembled between the guide patterns neighboring each other, and 
 the plurality of the second pillars surround one of the guide patterns or one of the first pillars. 
 
     
     
       4. The method of  claim 3 , wherein the second pillars are self-assembled on central points of 2, 3 or 4 of the first pillars. 
     
     
       5. The method of  claim 3 , wherein the second self-aligned pattern is divided into first portions each of which is self-assembled at a peripheral portion of one of the first openings, and a second portion self-assembled at an outside of the guide patterns. 
     
     
       6. The method of  claim 5 , wherein:
 each of the first portions of the second self-aligned pattern has a ring shape laterally surrounding one of the first pillars of the first self-aligned pattern, and 
 the second pillars of the first self-aligned pattern are buried in the second portion of the second self-aligned pattern. 
 
     
     
       7. The method of  claim 3 , wherein forming the preliminary holes includes removing the first pillars and the second pillars. 
     
     
       8. The method of  claim 2 , wherein the first polymer unit includes polymethylmethacrylate (PMMA), and the second polymer unit includes polystyrene (PS). 
     
     
       9. The method of  claim 1 , further comprising forming a neutral layer along a surface of the object layer and along multiple surfaces of each of the guide patterns before forming the self-aligned layer. 
     
     
       10. The method of  claim 1 , wherein forming the plurality of the guide patterns includes:
 forming a plurality of sacrificial layer patterns on the object layer, each of the sacrificial layer patterns having a pillar shape; 
 forming a guide layer along surfaces of the object layer and the sacrificial layer patterns; 
 partially removing the guide layer to form the guide pattern surrounding a sidewall of each of the sacrificial layer patterns; and 
 removing the sacrificial layer patterns. 
 
     
     
       11. The method of  claim 10 , wherein partially removing the guide layer includes removing portions of the guide layer formed on top surfaces of the object layer and the sacrificial layer patterns by an etch-back process. 
     
     
       12. The method of  claim 1 , wherein forming the plurality of the guide patterns includes:
 forming an intermediate layer on the object layer; 
 forming a plurality of sacrificial layer patterns on the intermediate layer, each of the sacrificial layer patterns having a pillar shape; 
 partially etching the intermediate layer using the sacrificial layer patterns to form a plurality of intermediate layer patterns that each have a pillar shape; 
 removing the sacrificial layer patterns; 
 forming a guide layer along surfaces of the object layer and the intermediate layer patterns; 
 partially removing the guide layer to form a guide pattern surrounding a sidewall of each of the intermediate layer patterns; and 
 removing the intermediate layer patterns. 
 
     
     
       13. The method of  claim 12 , wherein the intermediate layer serves as an anti-reflection layer, and the sacrificial layer patterns include a negative-type photoresist material. 
     
     
       14. The method of  claim 12 , wherein partially etching the intermediate layer using the sacrificial layer patterns includes partially removing an upper portion of the object layer such that a stepped portion protruding from a top surface of the object layer is formed under each of the intermediate layer patterns. 
     
     
       15. The method of  claim 14 , wherein each of the guide patterns surrounding the sidewall of an intermediate layer pattern also surrounds a sidewall of a stepped portion corresponding to the intermediate layer pattern. 
     
     
       16. The method of  claim 1 , wherein forming the plurality of the guide patterns includes:
 forming a sacrificial layer pattern that includes a plurality of openings therein on the object layer; 
 forming a guide layer on sidewalls and bottoms of the openings; 
 removing portions of the guide layer which are formed on the bottoms of the openings to form one of the guide patterns on the sidewall of each of the openings; and 
 removing the sacrificial layer pattern. 
 
     
     
       17. The method of  claim 16 , further comprising:
 forming an intermediate layer on the object layer before forming the sacrificial layer pattern; and 
 partially removing the intermediate layer through the openings such that the openings are extended to expose the object layer. 
 
     
     
       18. The method of  claim 17 , further comprising partially etching an upper portion of the object layer exposed by the extended openings. 
     
     
       19. The method of  claim 17 , wherein the intermediate layer serves as an anti-reflection layer, and the sacrificial layer pattern includes a positive-type photoresist material. 
     
     
       20. A method of forming holes, the method comprising:
 forming a sacrificial layer pattern on an object layer, the sacrificial layer pattern including a plurality of pillar patterns or a plurality of openings; 
 forming a guide layer along the object layer and the sacrificial layer pattern; 
 partially removing the guide layer to form guide patterns spaced apart from each other, each of the guide patterns having a ring shape; 
 removing the sacrificial layer pattern; 
 forming a self-aligned layer on the object layer to fill the guide patterns; 
 partially removing portions of the self-aligned layer which are self-assembled inside the guide patterns and between the guide patterns neighboring each other to form preliminary holes; and 
 partially removing the object layer through the preliminary holes.